Thermostat electric control device



June 4, 1929. E, RlbER 1,715,676

THERMOSTAT ELECTRIC CONTROL DEVICE Filed March 7, 1928 I INVENTOR Herbert E Ride?" HIS A TORN Patented June 4, 1929.

UNITED STATES PATENT OFFICE.

HERBERT E. RIDER, OF NEW YORK, N. Y., ASSIGNOR, BY DIRECT AND MESNE ASSIGN- MENTS, OF THIRTY-FOUR PER GENT TO EMIL BLAIR, EIGI-ITEEN PER CENT TO CLINTON T. REVERE, AND EIGHTEEN PER CENT TO GEORGE C.'SHUBERT, ALL OF NEW YORK, N. Y.

THERMOSTAT ELECTRIC CONTROL DEV ICE.

Application filed March 7,

to provide a plug construction which may be easily attached to and detached from the article to be heated.

A further object is to provide means where by the switch mechanism may be adjusted from the exterior of the switch-casing to cause it to act at any given temperature within the radius of its capacity.

The invention is embodied in a casing oi: insulating material and is made and sold as a separate article of manufacture.

Referring to the drawings which form a part of this specification:

Fig. 1 is an elevational view of a plug embodying my invention, one half part of the casing being removed to disclose the arrangement of the mechanism of the plug, and a portion of the opposite half of the casing being shown to illustrate parts carried thereby.

Fig. 2 is an exterior view of the casing.

Fig. 3 is a cross-sectional view on line 33 of Figure 1.

Fig. 4 is a cross-sectional View taken on the offset lines 4-4 of Figure 1.

Fig. 5 is a vertical sectional view taken on line 55 of Figure 1.

The casing comprises two parts substantiallv alike in exterior form and dimensions. indicated by A and A respectively, and made of plastic electrical insulating material.

The two parts of the casing are held together by nut and bolt elements BB respectively, which pass through holes formed therein as shown.

The'upper end of the casing is provided with an opening C, and grooves C-C respectively, to hold the insulated electrical conductors D-D respectively, which are connected to binding posts EE, which also serve to hold said conductors to the leafswitch members F--F respectively, said leaf members being supported in channels G-G, formed in the adjacent faces of the casing as illustrated. The free ends F of the members .FF are curved outwardly to provide curved surface contact areas for easy. engagement with the T-shaped switch member H which is made of, insulating material and is pro vided with metal switch members H-H 1928. Serial No. 259,723.

respectively and carried in pivotable relation to the casing and secured thereto by a screw I, which screws into a bushing I as shown. Two channels J-J respectively are formed in the casing. one on each side of the chamber K formed in the middle part of the casing, and conductors L and L formed rectangular in cross-section, are located in these channels and extend across the contacting face portions of the casing, and serve to prevent relative lateral movement of the two side portions forming the casing and the upper ends also serve as contactportions for coaction with the switch member H. The lower ends of the elements L and L extend into separate chambers MM respectively, which chambers have openings M-M' as shown. Springjaw clips N and N respectively are located in the chambers M and connected rigidly to the lower end of the respective conductors L and L. The member N is provided with a lug N on one side which is provided with a wide fiat surface adapted to rest in contact with a similar surface formed on a metal sheet P carried on the side of the thermostat member P and extending the entire width of same and serving to conduct heat from the jaw member N to the thermostat member P. The thermostat element 1 comprises two sheets of metal suchas iron and brass, joined together in the usual manner, and connected to the portion A of the casing near its lower end by a rivet R, and the longer leaf is provided with a box S, held thereto by a screw S, and said box is provided with a cylindrical bore S in which is located a helical spring S with a ball S held in the upper end of said bore and free to move therein against the pressure of said spring. The pressure of the spring against the ball can be regulated by the adjustment thumbscrew T which screws into the lower end of said bore, and the wheel portion of which extends through a slot A formed in the side portion A of the casing. Two detents V and V formed to conformto the surface of the ball S, are made in the portion A of the casing as illustrated, and it will be observed that none of the working parts of the mechanism are mounted on this portion of the casing except these detents, all the working mechanism and anchored parts being carried by the side portion A of the casing. The wall portion between the two detents serves as an abutment, the function of which will be presently described.

The top end of the thermostat leaf P, is

bent at a right angle to the plan'esurfa'ce:

thereof and is slotted at V, anda pin H carried by the lower arm of the element H, ex-

. ilar two-point contact is made between the members F and L, when the adjacent switch member H is in position as shown, and which is the closed circuit position. A coiled wire guard W is held by the casing as shown, to protect the conductors from injury.

It will be noted that when the two parts of the casing, A and A are separated, the conducting elements L and L may be freely removed and all' working parts readily inspected. This permits of easy renewal 'of the jaw-members and switch parts integrally connected therewith.

The operation is as follows:

Assuming the switch to be closed, as illustrated in Figure 1, and the jaw-members N and Nconnected to the terminals of an electric sad-iron to be heated by the current supplied to a conductor D, thecurrent will flow through one of the elements H and L, and N, to the heating coil in the sad-iron and return through elements N, L, H and G to the return conductor D. When the sad-iron is heated to the, proper degree, the heat from the iron is conducted through the jaw-member N and member N 2 to the thermostat to cause the thermostat to bend and finally overcome the resistance of the ball S, and the top end of the thermostat will then snap over and carry the ball to the socket V, where it will be held until the thermostat cools to a predetermined degree. In making the movement above set forth, the top end of the i thermostat presses against the pin H and swings the T-shaped member H to the right, causing the contacts H respectively to simultaneously break the circuit and holding ball pressed spring, when it willsnap back to again close the switch, as willbe readily un-.. derstood.

against the ball by means of the screw T, the tuning of the action of the switch relative to the temperature of the thermostat, is regulated and controlled.

Some other form of abutment means in place of the ball and socket to perform its functions may bev used, but I have found in practice that the ball arrangement will act in a more perfect manner, due to the delicacy By adjusting the pressure of the spring with which the adjustment may be made,

whereby a wider range of temperatures may be controlled accurately, and the construction set forth has liable.

Having thus described claim as new:

A plug ofvthe character described, comprising a separable casing, a double-pole switch member supported therein, a thermy invention, I

-1nostat connected therewith in operative relation, jaw-members spaced from each other a predetermined distance, electrical conductors connected to said jaw-members and in permanent contact with the contacts of said switch member, switch members adapted to be connected with a source of electrical supply, and located adjacent said electrical conductors at a predetermined distance therefrom and in the path of said double-pole switch members, heat from one of said jaw-members to said thermostat and adjustable means for restraining the time movement of said thermostat in both directions, 1 comprising two sockets formed in the Wall of the casing and spaced from each other a predetermined distance, a cage carried on the thermostat, a helical spring in said cage, a ball carried by the cage in contact with said spring and adapted to seat in said sockets, and a screw carried by the cage and operative to press the spring as set forth.

In testimony whereof I have afiixed my signature.

HERBERT E. RIDER.

proved durable and rep and means for conducting 

